1. Field of the Invention
This invention relates to equipment for treating and conditioning water. More particularly, the invention relates to devices for filtering undesired substances from water, and to devices intended to add nutrients and/or minerals to water used for horticultural purposes.
2. Description of Background Art
It is often required or desired to remove certain impurities from water to be used for human consumption. For example, water supplied to residences by municipal water works often contains naturally occurring organic matter which, while not necessarily harmful, can impart an undesirable taste to the water. This is especially true during summer months in which algae and vegetation in the lakes and rivers supplying water to a municipal system proliferate.
In addition to the innocuous but noxious organic matter which is sometimes contained in water supplied to homes and businesses, the water can sometimes contain more hazardous substances. These can include agricultural pesticides and herbicides which run off cultivated lands and contaminate sources of water destined for treatment and ultimate human consumption. Also, industrial chemicals sometimes find their way into the water supply.
Besides those foreign substances which can degrade the quality of water, certain chemicals are added to water by municipalities to reduce the bacteria count of the water to safe levels. Until recently, chlorine was used almost exclusively for this purpose.
Water containing chlorine is readily conditioned to make it safe for tropical fish. The procedure simply requires filling the tank with chlorinated water and allowing the water to stand in the tank for approximately 24 hours before putting fish into the tank. That period is usually sufficient to permit chlorine in the water to evaporate.
Now, however, many municipalities are adding chemicals known as chloramines to the water instead of chlorine, to achieve the desired germicidal effect. Water containing chloramines has a deleterious effect upon the operation of kidney dialysis machines, as well as on fish. The removal of chloramines can be a time consuming and cumbersome process, requiring as long as 30 days. Typically, the chloramine removal process requires adding a chemical to the water which decomposes the chloramines into ammonia and chlorine. The chlorine gas is then allowed to evaporate from the water. Finally, a zeolite must be added to the water to absorb the ammonia, a step that can require many days to be fully effective. Accordingly, a need exists for a water filtration apparatus which can effectively and rapidly remove chloramines from water, as well as naturally occurring and man-made substances.
Since there is no simple and cost-effective method of removing every type of foreign substance in a single filtration operation, it is usually required to conduct water through a series of individual filters, each particularly suited to removing a specific class of foreign substances from the water. Therefore, it would be desirable to have a water filtration apparatus which was modular in design, permitting the ready interconnection in series of those filter assemblies specific to each particular class of foreign substances it desired to remove from the water.
In all common flow-through water filters, there is an inherent pressure drop, due to the resistance of the filter media to the flow of water. When water filter assemblies are cascaded, i.e., connected in series, the pressure drops across the input to output port of each filter assembly are additive. This can result in a substantial loss of output pressure when multiple filter assemblies are cascaded. Accordingly, it would be desirable to have a filter apparatus in which multiple filters could be connected in series without causing an excessive cumulative pressure drop, or loss of pressure head.
In providing water for irrigating landscape foliage or crops, it is frequently necessary to add plant nutrients and/or mineral supplements to the water. For such applications, it would be desirable to have an apparatus which can efficiently add desired substances for enhancing the growth of plants to water issuing from the apparatus.
The present invention is responsive to the desired attributes of a water filtration and conditioning apparatus set forth above. How the invention fulfills the needs alluded to will become apparent from the description of the invention which follows.